Field of the Invention
The present invention relates to a heater and tip assembly for use in soldering and desoldering systems. More specifically, the present invention relates to a heater-sensor subassembly for a soldering iron or desoldering tool for use environments requiring a soldering tip or desoldering tip with a high thermal capacity adapted for use in working electrical components designed to allow high current utilization.)
Descriptions of Related Art
Certain specialty automobile electrical parts for use in Electric Vehicles (EVs) and Hybrid Electric Vehicles (HEVs) as well as power supply components such as power conditioners used in solar power generation require very high thermal capacity when soldering because the required current flow to heat the soldering device is very high, and the parts to be soldered, sometimes referred to as the land of the substrate, are generally large and as a result the parts have a high thermal capacity.
Therefore, in the field of soldering large parts that are designed for high currents, there is a problem in that the solder does not melt properly, or workability is very bad with conventional soldering equipment. The heater sensor complex with high thermal capacity is required because heater sensor complex can be fabricated with 2 leads with sensing function.
An exemplary prior art soldering iron heater assembly described in U.S. Pat. No. 6,054,678 (Japanese Patent 3124506), hereby incorporated by reference, is depicted in FIGS. 1 and 2. The principal part of the soldering iron heater according to the prior art included a cylindrical insulating pipe having an axial bore and a heater-sensor complex mounted thereon. The insulating pipe may, for example, be an alumina pipe. FIG. 1 to illustrates the main components of the prior art heater-sensor complex, including a distal tip of a coil-shaped heating wire 3 welded to a distal tip of a linear non-heating wire 4 by argon welding. The base or proximal end of the heating wire 3 is welded to a linear non-heating wire 5. The heating wire 3 was made of iron-chromium alloy. Among such iron-chromium alloys, kanthal D (a kanthal wire manufactured by Kanthal Co.) was preferred. The proportions of its principal constituent elements are Cr=22.0 and Al=4.8. Such alternative compositions as Cr=22.0, Al=5.8, Cr=22.0, Al=5.3, and Cr=20.0, Al=4.0 can also be employed.
FIG. 2 depicts the heater-sensor complex of FIG. 1 as configured in a soldering iron tip assembly. The non-heating wire 4 is passed into and through the bore of an insulating pipe and the heating wire 3 is wound around the periphery of the insulating pipe forming a coil, with the respective distal ends secured together to form a thermocouple. The coil is secured to the insulating pipe and then the heater assembly including the thermal couple is inserted into and secured within a tip 9, having an axial bore that extends over the coil portion of the heater assembly to conduct heat to the distal end of the tip 9. In this configuration, the thermocouple is used to determine the tip temperature 1 and the coil is positioned as close as possible to the distal end of the tip.
FIG. 3 depicts a mechanical drawing of an exemplary heater-sensor complex made according to the teachings of the a prior art of FIGS. 1 and 2, depicting the coil having a length of about 10.5 mm extending proximally from a position about 1.5 mm from the distal end of the insulating pipe and within 3.5 mm of the end of the thermocouple. This assembly was configured for use in the handle assembly as depicted in FIG. 7 of the U.S. Pat. No. 6,054,678. The products made according to the design have been well received in the marketplace and as a result there are a substantial number of power stations and handles for use with the cartridges having the design in use in the industry. The configuration is very well adapted to use with small works, such as electrical circuit boards and fine wire electrical components. These types of works require precise temperature control of the soldering tip, and rapid heating of the tip by the application of power to the coil.
While the configuration according to the prior art U.S. Pat. No. 6,054,678 has been very well received and exceptionally adapted for use with small works, the soldering cartridges are not as well suited for use with large works, as for example the electrical parts for use in EVs and HEVs as well as power supply components such as power conditioners used in solar power generation. Accordingly, the present invention contemplates a soldering cartridge design and heater-sensor assembly having a very high thermal capacity for use with works having large surface areas, and which are useable with the installed base of soldering stations configured for use with the cartridges of the prior design.